In the field of bicycles, it is well known that there are many different configurations of wheel rims, brake pad assemblies and brake pad holders. Due to the many configurations of these and other associated parts of bicycles, it is well known that it is desirable to provide some means for adjusting the relative position of the brake pad with respect to the wheel rim. Other factors that render such adjustability desirable include wearing of the brake pad surface, and adjustments in tension in the brake cables for various riding conditions.
Many different brake pad arrangements have been provided in the prior art. Included are unitary brake pads which include a mounting arm integrally formed with a brake pad. Conventionally, the brake pad is fabricated from a material, such as rubber, which yields a relatively high coefficient of friction against the surface of the wheel rim when the brakes are applied. In these unitary constructions, when the brake pad becomes sufficiently worn, the entire device, including the mounting arm, must be replaced. The following U.S. patents are illustrative of the prior art. Several of these disclose devices wherein the mounting arm is fixed relative to the brake pad. Others disclose intricately formed constructions wherein the mounting arm is adjustable relative to the brake pad.
U.S. Pat. No. Des. 384,018 issued to T. Noshimura discloses a design for a cantilever brake for a bicycle. Although not clearly depicted in the figures, it is apparent that the mounting arm and brake pad holder are mounted in a fixed position. Noshimura does not disclose a means for altering the relationship between these two components.
U.S. Pat. No. 4,051,924 issued to K. Yoshigai discloses a device for mounting a brake shoe to a brake of a bicycle. Yoshigai teaches a means for varying the position of the brake shoe with respect to the brake arch similar to that illustrated in Prior Art FIG. 1 described below. However, the '924 device includes a brake shoe in which the mounting arm and brake pad holder are mounted to each other in a fixed relation.
Similar to the previous device, U.S. Pat. No. 4,444,294, also issued to T. Yoshigai, discloses a brake shoe mount which allows adjustability of the brake pad only in one degree of movement. Specifically, the brake pad is rotatable about an axis parallel to the brake pad mounting arm. As in the previous device, the mounting arm is mounted in a fixed position relative to the brake pad.
U.S. Pat. Nos. 4,441, 592 and 4,611,692 issued to R. C. Everett disclose bicycle brake assemblies including a brake pad which has a rigid internal member embedded therein. A mounting arm is received through the internal member and protrudes from the brake pad for mounting the brake pad to a brake assembly. The internal member defines a concave exposed surface circumventing the post. A washer defining a convex surface to cooperate with the internal member concave surface and an opposing flat surface is interposed between the brake pad member and the brake caliper arm. A washer having one flat surface and one concave surface is disposed on an opposite side of the brake caliper arm, and a nut having a convex end to cooperate with the concave side of the second washer is tightened on the brake pad post. The cooperating concave and convex surfaces allow adjustability of the brake pad with respect to the brake caliper arm. As illustrated, the post is fixed relative to the brake pad. Further, the brake pad may not be replaced independently from the post, thereby increasing maintenance costs.
U.S. Pat. No. 4,901,823 issued to M. Chang discloses an adjustable brake pad mount. The brake pad mount includes a mounting arm which is adjustably, yet permanently, mounted onto the brake pad. The mounting arm is a bolt having a head with a top convex surface and a lower concave surface. The interior of the brake pad defines a centrally disposed concave surface to cooperate with the convex upper surface of the mounting arm head. A positioning member defines a convex portion for cooperating with the concave lower service of the mounting arm head. The positioning member is either embedded within the brake pad or permanently secured to exterior of the brake pad. To wit, the brake pad is not replaceable independently of the mounting arm.
U.S. Pat. Nos. 5,547,046 issued to Z. M. Chen and U.S. Pat. No. 5,636,716 issued to M. Sugimoto, et al., each disclose a brake assembly having a means for mounting a brake pad on a brake pad caliper in a manner similar to that illustrated in the Prior Art FIG. 1 described below. The brake pad and mounting arm are fixed relative to each other.
U.S. Pat. No. 5,655,629 issued to S. Takizawa, et al., is a bicycle brake shoe having a brake pad holder, or main body, and a mounting arm, or fixing pin. The mounting arm is mounted to the brake pad holder in a fixed position.
Another type of brake pad holder includes a brake pad mount for removably receiving a brake pad. A typical brake pad holder 100 of this type is illustrated in the Prior Art FIG. 1. A mounting arm 106 is fixed to the brake pad mount 104. The brake pad mount 104 defines a channel for receiving the brake pad 102. The brake pad 102 includes a recessed portion 126 in the underside for receiving a pin (not shown). To this extent, the brake pad mount 102 defines an opening 128 proximate the brake pad recessed portion 126 for cooperating with the pin. The pin defines a length to extend at least partially into the brake pad recessed portion 126 to prevent the brake pad 102 from sliding out of the brake pad mount channel.
A pair of cooperating washers 108,112 is disposed on either side of the brake caliper arm (not shown). Each pair of cooperating washers 108,112 includes one washer 112 having a convex side 114 and another washer 108 having a cooperating concave side 110. The outer sides of each pair of washers 108,112 defines a flat side to abut either of the brake pad mount 106, the brake caliper arm, or a nut 124. Thus, the orientation of the brake pad 102 may be altered with respect to the brake caliper arm as a result of the relative movement between the cooperating pairs of washers 108,112, as illustrated by the arrows 116,118. The nut 124 is secured to the end of the mounting arm 106 in order to secure the brake pad mount 104 once the desired orientation of the brake pad 102 is achieved. However, because the mounting arm 106 is disposed at an acute angle with respect to the brake caliper arm, the brake pad mount 104 has a tendency to loosen after repeated application of the brakes.
The prior art disclosed above does not provide a brake assembly wherein the brake pad orientation is adjustable with respect to the wheel rim, with the mounting arm remaining in an orthogonal orientation with respect to the brake caliper arm, and with the brake pad being independently replaceable.
Therefore, it is an object of this invention to provide a means for adjustably mounting a bicycle brake pad to a brake caliper arm.
Another object of the present invention is to provide such a device whereby the mounting arm of the brake pad mount remains in an orthogonal orientation with respect to the brake caliper arm, while the brake pad holder is adjustable in three degrees of motion.
A further object of the present invention is to provide such a device whereby the brake pad is removable from the brake pad mount.